[f-nsp] NAT just dies.

[Dan Norton]

We have a serveriron XL running 7.400.

Twice in the last two months, NAT translations have completely failed
without warning and without any entries in the logs that point to
anything being wrong.

When we do a "show ip nat trans" there is usually only a single entry,
usually there are almost 100 at any one time.

A reboot fixes it.

Prior to each failure, no changes had been made for at least a week. The
configuration on this foundry is pretty static.

Has anyone seen this before?